1. Field of the Invention
The present invention relates to a steering column hanger beam for supporting a steering column for steering a vehicle.
2. Description of the Related Art
Vehicle such as automotive vehicles comprise a steering column hanger beam for supporting a steering column for steering. As to the steering column hanger beam, for example, Japanese Patent Examined Publication No. Hei. 7-85991 proposes a xe2x80x9csteering column support member mounting structure.xe2x80x9d
In this technique, a steering column support member (hereinafter, referred to as a xe2x80x9csteering column hanger beamxe2x80x9d) is extended transversely of the vehicle body, whereby the steering column is supported by this steering column hanger beam.
Since the steering column hanger beam is a member formed of a steel material, the rigidity can be maintained even if the beam is reduced to a relatively small diameter. Accordingly, since a relatively wide space can be secured with such a reduced-diameter beam, an accessory to the vehicle body such as an air conditioner can be disposed in this space.
In order to suppress the fuel consumption of an engine, however, the weight of the vehicle body needs to be reduced. In order to have a lighter vehicle weight, the vehicle body may be formed of a light material such as aluminum alloy.
Aluminum alloy provides a lower tensile strength when compared with steel, and therefore, in a case where the steering column hanger beam is produced of aluminum alloy, the diameter of such a steering column hanger beam has to be increased when compared with a steel steering column hanger beam in order to secure a required rigidity for the steering column hanger beam.
However, increasing the diameter of the steering column hanger beam makes it difficult to reduce the vehicle weight.
In addition, increasing the diameter of the steering column hanger beam then reduces the space in the vicinity thereof, and this may cause a risk of little space for placement of an accessory to the vehicle body such as an air conditioner being secured.
To this end, an object of the invention is to provide a technique with which not only the steering column hanger beam can be made lighter but also enough space can be secured for placement of an accessory to the vehicle body such as an air conditioner.
With a view to attaining the above object, according to a first aspect of the invention, there is provided a steering column hanger beam structure wherein a steering column hanger beam extended between left and right front pillars for supporting a steering column is constructed by an in-line connected body comprising in turn a driver""s side hanger beam having a large diameter cross-section and a front passenger""s side hanger beam having a small diameter cross-section.
The steering column hanger beam is provided which is the in-line connected body comprising the driver""s side hanger beam and the front passenger""s side hanger beam. Due to this, the driver""s side hanger beam which needs to provide a higher rigidity can be provided with the large diameter cross-section, whereas the front passenger""s side hanger beam which does not need to provide a relatively high rigidity can be provided with the small diameter cross-section.
Consequently, while the rigidity required for the steering column hanger beam is secured, the weight of the steering column hanger beam can be reduced.
In addition, the small diameter cross-section of the front passenger""s side hanger beam allows the relatively wide space to be secured in the vicinity of the hanger beam.
According to a second aspect of the invention, there is provided a steering column hanger beam structure, wherein the driver""s side hanger beam comprises a flange disposed at one end of a beam main body for abutment with one of the front pillars and support brackets disposed on a side of the beam main body for supporting the steering column, and wherein the beam main body, the flange and the support brackets are manufactured from extruded profiles.
The constituent components of the driver""s side hanger beam are manufactured of the extruded profiles. This allows the constituent components of the driver""s side hanger beam can be formed in a continuous fashion, respectively, and therefore, the production efficiency thereof can be improved.
According to a third aspect of the invention, there is provided a steering column hanger beam structure, wherein the beam main body is a long member having a rectangular cross-section.
The beam main body is formed so as to have the rectangular cross-section. The flange and the support brackets can be mounted at the proper position on the beam main body with ease by making use of corners of the rectangular cross-section. Consequently, the driver""s side hanger beam can be assembled with a relatively short period of time.